Plants & Animals

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From Missouri Conservationist: Aug 2011
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Prairie Crayfish

To survive life on the prairie, this crayfish burrows deep and comes out mostly at night.

Last summer I was photo-hiking along a trail at Shaw Nature Reserve in Franklin County when I noticed a crayfish crossing my path. I wasn’t too surprised to see the little critter because it had rained the entire evening before and I thought its burrow might have filled with water. Having never seen a burrowing crayfish, I made a closer inspection and found the specimen to be a female with a full nursery of young tucked beneath her abdomen. Irritated at my curiosity, the anxious mother raised her pincers in defense, warning me not to come any closer. At that point I backed off, spread my tripod flat on the ground and assumed my least favorite wildlife photography position—flat on my belly in the wet grass. I made my first images of what I later learned was a prairie crayfish (Procambarus gracilis) one of Missouri’s four burrowing crayfishes, a group that also includes the devil crayfish, digger crayfish and painted devil crayfish. I also determined that the trail on which I’d been hiking was in the vicinity of excellent prairie crayfish habitat, including a wetland, several ponds and a restored prairie.

Although the prairie crayfish is common in the grasslands of Missouri’s prairie region, they are seldom seen due to their secretive and nocturnal nature. Prairie crayfish make their homes in burrows, which must be deep enough to reach moist soil near the water table, sometimes six feet or more down. The mounds of soil that form around the burrow entrances are called chimneys. Prairie crayfish exit their tunnels in the evening or on rainy days to forage and find mates. Like other burrowing crayfish, the prairie crayfish is equipped with gills that are designed to obtain oxygen from the air for extended periods away from water as long as conditions are moist. Prairie crayfish feed on plants and insects and just about anything else they can find, dead or alive. After mating, the female lays her eggs in early spring. The female carries the eggs under her abdomen through two molts (when they shed their hard outside skeleton), at which time they begin to look like miniature versions of their mother as seen in the photograph. When the young are ready to face the world on their own, the mother drops them off at a pond, wetland or other moist habitat.

As I photographed the crayfish with all of her young in tow, I thought about how risky each trek from her burrow must be. I watched her respond frantically, pincers high in the air when a crow passed overhead. It is no wonder that this species prefers to venture out under the cover of darkness. After taking some images I continued down the trail but I eventually looked back to find several crows swooping over my previous location. I hoped the dutiful mother had made it into the tall grass, but then I thought to myself, “Crows have to eat, too.”

—Story and photo by Danny Brown

The Conservation Department's guidebook The Crayfishes of Missouri covers the habits, habitats and home ranges of 32 species of crayfishes. It features color photos and drawings to help identify these animals. This softcover book is available for $5 plus shipping and handling, and sales tax (where applicable) by calling toll free 877-521-8632 or visiting mdcnatureshop.com. (see Page 3 for regional phone numbers to call for a location near you).

This Issue's Staff

Editor In Chief - Ara Clark
Managing Editor - Nichole LeClair Terrill
Art Director - Cliff White
Staff Writer - Bonnie Chasteen
Staff Writer - Jim Low
Photographer - Noppadol Paothong
Photographer - David Stonner
Designer - Stephanie Thurber
Artist - Mark Raithel
Circulation - Laura Scheuler